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gomodules.xyz/nats-logr

Package natslogr

v0.1.0
Latest Go to latest
Published: Jul 10, 2019 | License: Apache-2.0 | Module: gomodules.xyz/nats-logr

README

nats-logr

A logr implementation using https://nats.io

Usage

Code Example

Description

To use nats-logr, you have to do the following:

  • Run the following in a window: $ nats-streaming-server --cluster_id=example-cluster
  • Run the following .go file in second window: “`go package main

import ( “fmt” “io” “os” “os/signal” “time”

"github.com/nats-io/stan.go"

)

func processMsg(msg *stan.Msg) { fmt.Printf(“Received on [%s]: ‘%s’\n”, msg.Subject, msg) msg.Ack() }

func logCloser(c io.Closer) { if err := c.Close(); err != nil { fmt.Fprintf(os.Stderr, “Close error: %v”, err) os.Exit(1) } }

func main() { conn, err := stan.Connect( “example-cluster”, “example-client-2”, stan.NatsURL(stan.DefaultNatsURL), stan.SetConnectionLostHandler(func(_ stan.Conn, reason error) { fmt.Fprintf(os.Stderr, “Connection lost, reason: “, reason) os.Exit(1) }), ) if err != nil { fmt.Fprintf(os.Stderr, “Can’t connect: %v.\nMake sure a NATS Streaming Server is running at: %s”, err, stan.DefaultNatsURL) os.Exit(1) } defer logCloser(conn)

fmt.Printf("Connected to %s clusterID: [%s] clientID: [%s]\n", stan.DefaultNatsURL, "example-cluster", "example-client-2")

sub, err := conn.QueueSubscribe(
	"nats-log-example",
	"test", func(msg *stan.Msg) {
		processMsg(msg)
	}, stan.SetManualAckMode(), stan.DurableName("i-remember"), stan.DeliverAllAvailable(), stan.AckWait(time.Second),
)
defer logCloser(sub)

ch := make(chan os.Signal, 1)
signal.Notify(ch, os.Interrupt)
<-ch

}

- Finally, run the following code in another window: 
```go
package main

import (
	"errors"
	"flag"
	"fmt"

	natslogr "gomodules.xyz/nats-logr"

	"github.com/nats-io/stan.go"
)

func main() {
	flag.Set("v", "4")
	flag.Parse()

	natslogr.InitFlags(nil)
	defer natslogr.Flush()

	opts := natslogr.Options{
		ClusterID: "example-cluster",
		ClientID:  "example-client",
		Subject:   "nats-log-example",
	}
	logger := natslogr.NewLogger(opts).
		WithName("Example").
		WithValues("withKey", "withValue")
	logger.Info("Log Example", "key", "value")

	logger.V(0).Info("Another Log Example", "logr", "nats-logr")

	logger.Error(errors.New("an error has been occured"), "error msg", "logr", "nats-logr")
}

Now, you will see the logs in the second window.

Acknowledgement

The logger parts of this library has been adapted from k8s.io/klog which itself is a fork of golang/glog.

Source: gomodules.xyz/nats-logr@v0.1.0/README.md